It should be possible if you want just a single solid colour with transparency.
Try creating a rule that sets cut fills to be 25% or 50% and be sure to set the background pen for cut fills to transparent (pen 0).
You can change the criteria to search just for columns if you want or you can be more specific by searching for columns in a certain layer with a certain building material, etc.
But if you want the column to have the structural concrete fill (triangles and dotted hatch) then you need to set that fill (or don't override the fill if it is already correct in your columns.
However you can only have a solid colour or fully transparent fill for the background.
You won't be able to have a semi-transparent coloured background.
As with any fill the background can only be solid coloured or fully transparent.
It is the foreground pen (or hatch pen) that provides an overlaying colour in the hatch pattern that you choose.
The % fills have a semi-transparent foreground hatch that will allow the background colour to show through.
If the background pen is set to transparent then you will see everything else behind that fill as well.
If the background pen is set to a colour then it will block anything behind it but a % of that background colour will show through the % hatch.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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